1) Field of the Invention
Embodiments of this invention relate to welding and, more specifically, to the removal of weld flash from a welded member, such as is typically formed during linear friction welding.
2) Description of Related Art
The term “weld flash” (or “flash”) generally refers to a material deposit formed near a weld joint as a result of material that is displaced from the joint during the welding operation. Weld flash can be formed during various types of welding including various types of friction welding such as friction stir welding, rotary friction welding, and linear friction welding. Friction welding is described in U.S. Pat. No. 5,460,317 to Thomas, et al. and U.S. Pat. No. 6,779,708 to Slattery, the entirety of each of which is incorporated herein by reference. The linear friction welding process described in U.S. Pat. No. 6,779,708 includes moving a joining member against one or more structural members in a generally linear motion. Friction between the members results in heating of their contacting surfaces, thereby plasticizing the material of the joining member and/or the structural member. After sufficient plasticization has occurred, the motion is terminated and a compressive force is typically maintained between the members while the plasticized material cools and hardens to form a joint between the members. As illustrated in U.S. Pat. No. 6,779,708, flash formed during linear friction welding can be formed as a bead or ridge-like formation extending longitudinally along the edge of the linear friction weld joint where the plasticized material has been extruded from the interface between the members being welded as a result of the compressive force therebetween. The flash can be formed as a continuous bead or multiple isolated deposits.
Weld flash, which is typically considered to be an undesired result of the welding operation, can be removed. For example, pliers can be used to grip the flash and manually pull the flash from the welded members, or the flash can be chiseled from the members. In some cases, flash can be removed by a computer-guided machining device, such as a CNC machine; however, it has been found that the flash tends to clog the tool or bit of such a machine and increase the likelihood of breaking the tool. Moreover, such operations add to the time and, hence, the cost of manufacturing. In some cases, the members being welded may need to be removed from the welding machine so that flash can be removed before completion of the welding, thereby further complicating the manufacturing process and increasing the time required for manufacture.
Thus, there exists a need for an improved apparatus and method for removing flash from structural members. The method should be compatible with friction welding operations and, in particular, linear friction welding operations. Further, the method should enable the flash to be removed without excessive machining and breaking of machining tools.